package com.hzqy.commons.utils;

import java.security.MessageDigest;

public class MD5Util {

	private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5",
		"6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
	
	private static String byteArrayToHexString(byte b[]) {
		StringBuffer resultSb = new StringBuffer();
		for (int i = 0; i < b.length; i++)
			resultSb.append(byteToHexString(b[i]));

		return resultSb.toString();
	}

	private static String byteToHexString(byte b) {
		int n = b;
		if (n < 0)
			n += 256;
		int d1 = n / 16;
		int d2 = n % 16;
		return hexDigits[d1] + hexDigits[d2];
	}

	public static String MD5Encode(String origin, String charsetname) {
		String resultString = null;
		try {
			resultString = new String(origin);
			MessageDigest md = MessageDigest.getInstance("MD5");
			if (charsetname == null || "".equals(charsetname))
				resultString = byteArrayToHexString(md.digest(resultString
						.getBytes()));
			else
				resultString = byteArrayToHexString(md.digest(resultString
						.getBytes(charsetname)));
		} catch (Exception exception) {
		}
		return resultString;
	}
	
/**
 * 
 * MD5-32位大写加密
 * 
 */
	public static String MD5_32bit(String token) {
		String result = "";
		 try {
			MessageDigest md5 = MessageDigest.getInstance("MD5");
			md5.update((token).getBytes("UTF-8"));  
			byte b[] = md5.digest();  
			int i;  
		    StringBuffer buf = new StringBuffer("");  
		      
		    for(int offset=0; offset<b.length; offset++){  
		        i = b[offset];  
		        if(i<0){  
		            i+=256;  
		        }  
		        if(i<16){  
		            buf.append("0");  
		        }  
		        buf.append(Integer.toHexString(i));  
		    }  
		    result = buf.toString().toUpperCase(); 
		} catch (Exception e) {
			 
		} 
		return result;
	}

	public static String MD5(String url) {
		try {
			// 得到一个信息摘要器
			MessageDigest digest = MessageDigest.getInstance("MD5");
			byte[] result = digest.digest(url.getBytes());
			StringBuffer buffer = new StringBuffer();
			// 把每一个byte 做一个与运算 0xff;
			for (byte b : result) {
				// 与运算
				int number = b & 0xff;// 加盐
				String str = Integer.toHexString(number);
				if (str.length() == 1) {
					buffer.append("0");
				}
				buffer.append(str);
			}

			// 标准的md5加密后的结果
			return buffer.toString();
		} catch (Exception e) {
			e.printStackTrace();
			return "";
		}
	}
}
